JP2024000695A - Stylet and urethral catheter set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stylet which achieves both excellent insertion performance into a urethral catheter and extraction performance, and excellent rigidity that can improve insertion performance into the urinary tract of the urethral catheter, and a urethral catheter set provided with the stylet.

SOLUTION: In a stylet 10 for urethral catheter, polyether ether ketone is contained as a material composing the stylet 10 to form a plurality of grooves 12 on an outer peripheral surface 10a of the stylet 10. A urinary tract catheter set uses the stylet 10 as the urethral catheter and the stylet inserted in the urethral catheter.

SELECTED DRAWING: Figure 2

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a stylet and urinary catheter set.

For patients who have difficulty urinating, a urinary catheter is inserted into the urethra and its tip is placed in the bladder, and the urine in the bladder is drained from the urine drainage port provided at the tip to a urine storage bag outside the body. In some cases, treatment is performed to discharge the phlegm (Patent Document 1).

The middle part of the urinary catheter that connects the funnel part (rear end part) placed outside the urethra and the tip part is made of flexible material to reduce the feeling of a foreign body or discomfort when inserted into the urethra. It consists of a tube.
In general, it is difficult to insert a urinary catheter with a flexible intermediate portion into the urethra as it is, so a stylet is inserted as a core material into the urethral catheter before insertion into the urethra (for example, Patent Document 2) . In particular, urinary catheters for children are thinner and softer than those for adults, and therefore require the use of a stylet.

JP2020-92911A Japanese Patent Application Publication No. 2013-233362

Conventionally, especially in the case of a silicone urinary catheter, there is a large resistance when inserting or removing a stylet, making it difficult to smoothly insert or remove the stylet. A known method for improving the insertability and removability of a stylet is to attach powder (corn starch, silicone powder, etc.) to the outer circumferential surface of the stylet to increase sliding properties. However, the task of uniformly applying powder to the entire outer peripheral surface of the stylet is complicated.
Further, it is important that the stylet has sufficient rigidity so as to sufficiently improve the insertability when inserting the urinary catheter into the urethra.

The present invention provides a stylet that has both excellent insertion and removal properties into a urinary catheter and excellent rigidity that can sufficiently enhance the insertion properties of the urinary catheter into the urethra, and a urethral tract equipped with the stylet. The purpose is to provide catheter sets.

The present invention includes the following configurations.
[1] A stylet for a urinary catheter,
The material constituting the stylet contains polyetheretherketone,
A stylet, wherein a plurality of recesses are formed on an outer peripheral surface of the stylet.
[2] The stylet according to [1], wherein the plurality of recesses include at least one of a groove and a depression.
[3] The stylet according to [1], wherein a plurality of grooves extending in the length direction of the stylet are provided as the plurality of recesses at intervals around a central axis of the stylet.
[4] The stylet according to [3], wherein the plurality of grooves are provided continuously from the tip to the rear end of the stylet.
[5] A urinary catheter set comprising a urinary catheter and the stylet according to any one of [1] to [4], which is inserted into the urinary catheter.

According to the present invention, there is provided a stylet that has both excellent insertion and removal properties into a urinary catheter and excellent rigidity that can sufficiently enhance the insertion properties of the urinary catheter into the urethra, and the stylet. A urinary catheter set can be provided.

It is a perspective view showing a stylet of an example of an embodiment. FIG. 2 is a cross-sectional view of the stylet of FIG. 1 taken in a direction perpendicular to its length; FIG. 2 is a cross-sectional view showing the stylet of FIG. 1 inserted into a urinary catheter. FIG. 2 is an enlarged cross-sectional view showing a groove (recess) formed on the outer circumferential surface of the stylet. FIG. 7 is a cross-sectional view of a stylet according to another example of the embodiment taken in a direction perpendicular to the length direction. FIG. 2 is a side view showing an example of a urinary catheter. FIG. 7 is a cross-sectional view of the urinary catheter of FIG. 6 taken along a plane including its central axis. FIG. 7 is an enlarged cross-sectional view showing the vicinity of the tip when the stylet of FIG. 1 is inserted into the urinary catheter of FIG. 6;

Hereinafter, an example of the stylet and urinary catheter set of the present invention will be described based on the drawings. Note that the dimensions of the figures illustrated in the following description are merely examples, and the present invention is not necessarily limited thereto, and can be practiced with appropriate changes within the scope of the gist thereof. .

[Stylet]
As shown in FIG. 1, the stylet 10 is a long and thin rod-shaped member.
The stylet 10 is a stylet for a urinary catheter. That is, the stylet 10 is inserted into a urinary catheter as a core material when the urinary catheter is inserted into or removed from the urethra.

The stylet 10 of the example shown in FIGS. 1 and 2 has a plurality of grooves (recesses) 12 extending in the length direction of the stylet 10 on the outer peripheral surface 10a of a rod-shaped body having a substantially circular cross section. They are formed at intervals around the circumference.
By forming the groove 12 on the outer circumferential surface 10a of the stylet 10, the contact area between the outer circumferential surface 10a of the stylet 10 and the inner surface of the urinary catheter becomes small when the stylet 10 is inserted into the urinary catheter. Therefore, the resistance when inserting the stylet into the urinary catheter or when removing the stylet 10 from the urinary catheter is reduced. As a result, even if the catheter is made of silicone, the stylet 10 can be inserted and removed smoothly.

It is preferable that the groove 12 formed in the outer circumferential surface 10a of the stylet 10 is formed continuously from the tip to the rear end of the stylet 10. This reduces the resistance when inserting or removing the stylet, and allows the stylet to be inserted or removed more smoothly. Note that each groove 12 is not limited to being formed continuously from the tip to the rear end of the stylet 10, and may be formed intermittently.

Preferably, the plurality of grooves 12 are formed at equal angular intervals around the central axis of the stylet 10. This reduces the resistance when inserting or removing the stylet, making it easier to smoothly insert or remove the stylet.

When the stylet 10 of this example is cut in a direction perpendicular to the length direction, the outer peripheral shape has a wave shape that goes around the central axis.
Further, when each groove 12 in this example is cut in a direction perpendicular to the length direction, the surface shape is a curved line with an inflection point on the way from each opening edge on both sides of the groove to the bottom. There is. Note that the shape of each groove 12 is not limited to the shape of this example.

The number of grooves 12 formed on the outer circumferential surface 10a of the stylet 10 is preferably four or more, and more preferably eight or more. If the number of grooves 12 is equal to or greater than the lower limit, the resistance to insertion or removal of the stylet into or out of the urinary catheter will be reduced, and the effect of smooth insertion or removal is likely to be obtained. The number of grooves 12 is preferably 30 or less, more preferably 20 or less. If the number of grooves 12 is below the upper limit, sufficient rigidity is likely to be obtained, and the ease of inserting the urethral catheter into the urethra into which the stylet has been inserted is improved. The preferable lower limit and upper limit of the number of grooves 12 can be arbitrarily combined, and for example, 4 to 20 are preferable.

The maximum diameter of the stylet 10 is preferably adjusted so that the clearance between the stylet 10 and the urinary catheter is within an appropriate range when the stylet 10 is inserted into the urinary catheter. For example, as shown in FIG. 3, the stylet 10 is inserted into the main lumen 27 of a urinary catheter 20, which has a main lumen 27 that functions as a urinary tract and a sub-lumen 28 that functions as a flow path for fluid to inflate a balloon. In this case, the clearance between the stylet 10 and the urinary catheter 20 is _determined by the _difference (D _min −D _max ).
D _min −D _max is preferably 0.05 mm or more, more preferably 0.1 mm or more. If D _min -D _max is equal to or greater than the lower limit value, smooth insertion and removal with little resistance is possible. D _min −D _max is preferably 0.8 mm or less, more preferably 0.6 mm or less. If the difference (D _min −D _max ) is less than or equal to the upper limit value, sufficient rigidity can be obtained.

The ratio (W/D _max ) of the width W of the groove 12 to the maximum diameter D _max of the stylet 10 is preferably 0.01 or more, and more preferably 0.05 or more. If W/D _max is equal to or greater than the lower limit, the resistance when inserting or removing the stylet from the urinary catheter becomes small, and the effect of smooth insertion or removal is likely to be obtained. W/D _max is preferably 0.6 or less, more preferably 0.2 or less. If W/D _max is below the upper limit, sufficient rigidity is likely to be obtained, and the urethral catheter with the stylet inserted can be smoothly inserted into the urethra. By making the outer shape of the stylet into a shape close to a circle, balanced rigidity can be obtained, and sliding properties can be increased by an appropriate number of protrusions provided between the grooves.
However, as shown in FIG. 4, the width W of the groove 12 is the distance between the tangent line k that touches the convex parts on both sides of the groove 12 and the contact points a and b between the tangent line k and the convex parts on both sides. means.

The ratio (D/D _max ) of the depth D of the groove 12 to the maximum diameter D _max of the stylet 10 is preferably 0.01 or more, and more preferably 0.05 or more. If D/D _max is equal to or greater than the lower limit, the resistance to insertion or removal of the stylet into or out of the urinary catheter will be small, and the effect of smooth insertion or removal is likely to be obtained. D/D _max is preferably 0.25 mm or less, more preferably 0.1 or less. If D/D _max is below the upper limit, sufficient rigidity is likely to be obtained, and the insertability of the urethral catheter into the urethra with the stylet inserted will be improved. The preferable lower and upper limits of D/D _max can be arbitrarily combined, and are preferably 0.05 to 0.1 mm, for example.
However, as shown in FIG. 4, the depth D of the groove 12 means the distance between the tangent k touching the convex portions on both sides of the groove 12 and the deepest part of the groove 12.

The stylet 10 is set to be longer than the total length of the urinary catheter. As a result, even when the stylet 10 is inserted to the tip of the urinary catheter, the rear end portion of the stylet 10 is exposed to the outside from the rear end opening of the funnel portion of the urinary catheter. Therefore, it becomes easier to grasp and remove the exposed portion of the stylet inserted into the urinary catheter.

The material making up the stylet 10 contains polyetheretherketone (PEEK). By containing PEEK, the stylet 10 has excellent rigidity, so that the urinary catheter has sufficient insertability into the urethra when inserted into the urethral catheter.
Preferably, the stylet 10 is made only of PEEK. Note that the material constituting the stylet 10 may include a resin other than PEEK, as long as it does not impair the effects of the present invention. Examples of other resins include polybenzimidazole (PBI), polyamide (PA), and fluororesin. As other resins, one type may be used alone, or two or more types may be used in combination.

The method for manufacturing the stylet 10 is not particularly limited.
For example, a rod-shaped stylet can be formed by extrusion molding.

As explained above, since the stylet 10 has a plurality of grooves 12 formed on the outer peripheral surface 10a, the contact area with the inner surface of the urinary catheter within the urinary catheter is larger than that of a stylet without grooves. resistance during insertion or removal. Therefore, even with a silicone urinary catheter, the stylet can be smoothly inserted and removed. Furthermore, since the stylet 10 contains PEEK, it has excellent rigidity and can sufficiently improve the insertability of the urethral catheter into the urethra. In this way, the stylet 10 has both excellent insertion and removal properties into the urinary catheter and excellent rigidity that can sufficiently improve the insertion properties of the urinary catheter into the urethra.

Note that the stylet of the present invention is not limited to the stylet 10 described above.
For example, a plurality of annular grooves may be formed on the outer peripheral surface of the stylet over the entire circumference in the circumferential direction at intervals in the length direction of the stylet.

Further, the stylet of the present invention may have a plurality of recesses formed on the outer circumferential surface, and the recesses are not limited to grooves. For example, as shown in FIG. 5, a stylet 10A may be provided in which a plurality of depressions 20A having a substantially semicircular cross section are formed in the outer peripheral surface 10a. It is preferable that such depressions are formed evenly in the length direction of the stylet 10A from the tip to the rear end. Note that the cross-sectional shape of the depression is not limited to a substantially semicircular shape, and may be substantially triangular, substantially rectangular, or the like.
Further, the stylet of the present invention may have both grooves and depressions formed on the outer peripheral surface.

[Urethral catheter set]
The urinary catheter set of the present invention includes a urinary catheter and a stylet of the present invention inserted into the urinary catheter.
The urinary catheter set of the present invention can employ any known configuration except for the stylet of the present invention.

(Urethral catheter)
A urinary catheter is a long tube-shaped medical device that is inserted into the urethra to drain urine from the bladder to the outside of the body. As the urinary catheter, any known urinary catheter can be used without any particular restriction.

An example of the urinary catheter is the urinary catheter 20 shown in FIGS. 6 and 7, for example.
The urinary catheter 20 of this example has a distal end portion 21 that is indwelled in the bladder, a funnel portion 22 that can be connected to a urine collection bag (urine storage container) outside the urethra, and a tubular shape that connects the distal end portion 21 and the funnel portion 22. and a balloon 24 provided on the outer surface of the distal end portion 21.

The distal end portion 21 of the urinary catheter 20 is a short tube with a hemispherical tip.
A urine drainage port (side hole) 21a is formed on the outer surface of the distal end portion 21 to introduce urine in the bladder into the catheter. The urine drainage port 21a is formed closer to the distal end than the portion of the outer surface of the distal end portion 21 where the balloon 24 is provided.
The number of urine drainage ports 21a may be one, or two or more.

The funnel portion 22 includes a first port 25 and a second port 26 branching from a side surface near the tip thereof. The first port 25 is a port for connecting to a urine storage bag via a connector or the like. The second port 26 is a port for connecting via a connector or the like to a liquid feeding device (such as an indeflator) that can feed fluid for inflating the balloon.

The intermediate portion 23 is made of a flexible tube.
The intermediate portion 23 in this example is a double tube having an outer tube 23a and an inner tube 23b inserted into the outer tube 23a.

The outer tube 23a and the balloon 24 in this example are integrally formed by a single tubular member 31.
The distal end portion of the tubular member 31 is externally fitted onto the rear end of the distal end portion 21 and joined in a liquid-tight manner, and the rear end portion of the tubular member 31 is externally fitted onto the distal end portion of the funnel portion 22 and joined in a liquid-tight manner. . In the distal end portion of the tubular member 31, the portion between the outer tube 23a and the balloon 24 and the distal end of the balloon 24 are fluid-tightly joined to the outer surface of the distal end portion 21 over the entire circumference around the axis. has been done. When fluid is supplied between these two joints, the balloon 24 is inflated.
Note that the outer tube 23a and the balloon 24 may be formed of separate members.

As shown in FIG. 7, in the urinary catheter 20, the inside of the distal end portion 21, the inside of the outer tube 23a of the intermediate portion 23, and the inside of the first port 25 of the funnel portion 22 are in communication with each other. A main lumen 27 is formed that functions as a urinary tract and communicates from the urinary opening 21a to the rear end opening of the first port 25.

Furthermore, the inner tube 23b of the intermediate portion 23 is connected at its rear end side to communicate with the flow path in the second port 26, and at its distal end side to communicate with the inside of the balloon 24. The inside of the inner tube 23b of the intermediate portion 23 and the inside of the second port 26 form a sub-lumen 28 that functions as a flow path through which fluid for inflating the balloon 24 flows.
Thus, the urinary catheter 20 in this example is a double lumen type catheter.

The outer surface of the outer tube 23a (tubular member 31) may be coated with an antibacterial coating, a hydrophilic coating, a water-repellent coating, or the like. The inner surface of the outer tube 23a may be coated with a water-repellent coating, a hydrophilic coating, or the like.
Examples of the antibacterial coating material include silver particles and zeolite silver particles. Examples of the material for the hydrophilic coating include N,N-dimethylacrylamide and polyvinylpyrrolidone. Examples of the material for the water-repellent coating include fluororesin.

When using the urinary catheter 20, the distal end 21 and intermediate section 23 are inserted into the urethra, and when the distal end 21 reaches the bladder, fluid is sent through the sublumen 28 to inflate the balloon 24, and the distal end 21 is inserted into the urethra. remains in place in the bladder. In this state, urine in the bladder is introduced into the urinary catheter 20 through the urine drainage port 21a provided at the distal end portion 21, and is discharged through the main lumen 27 to the urine storage bag outside the body.

The various dimensions of the urinary catheter 20 are not particularly limited, and may be set as appropriate depending on the intended use, such as for adults or children.
The materials of the distal end portion 21, intermediate portion 23, and balloon 24 of the urinary catheter 20 are not particularly limited, and include, for example, latex, silicone rubber, polystyrene thermoplastic elastomer, polyolefin thermoplastic elastomer, polyurethane thermoplastic elastomer, and vinyl. Examples include thermoplastic elastomers. Of these, latex and silicone rubber are preferred. These materials may be used alone or in combination of two or more.

As shown in FIG. 8, when inserting the stylet 10 into a urinary catheter 20, for example, since a plurality of grooves 12 are formed on the outer peripheral surface 10a of the stylet 10, the inner surface 20a of the urinary catheter 20 and The contact area with the outer circumferential surface 10a of the stylet 10 is small, and the insertion resistance is small. Further, the resistance when removing the stylet 10 from the urinary catheter 20 is also small. Therefore, the stylet 10 can be smoothly inserted into and removed from the urinary catheter 20.

The present invention is not limited to the embodiments described above, and the components in the embodiments described above can be replaced with well-known components as appropriate without departing from the spirit of the present invention. May be combined.

DESCRIPTION OF SYMBOLS 10, 10A... Stylet, 10a... Outer peripheral surface, 12... Groove (recess), 12A... Hollow (recess), 20... Urinary catheter, 21... Tip part, 22... Funnel part, 23... Intermediate part, 23a... Outer tube , 23b...inner tube, 24...balloon, 25...first port, 26...second port, 27...main lumen, 28...sublumen, 31...tubular member.

Claims (5)

A stylet for a urinary catheter,
The material constituting the stylet contains polyetheretherketone,
A stylet, wherein a plurality of recesses are formed on an outer peripheral surface of the stylet. The stylet of claim 1, wherein the plurality of recesses include at least one of a groove and a depression. The stylet according to claim 1, wherein a plurality of grooves extending in the length direction of the stylet are provided as the plurality of recesses at intervals around a central axis of the stylet. The stylet according to claim 3, wherein each of the plurality of grooves is continuously provided from the tip to the rear end of the stylet. A urinary catheter set comprising a urinary catheter and a stylet according to any one of claims 1 to 4 inserted into the urinary catheter.

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